Sewing machine



Nov. 19, 1940. R. BECKER SEWING MACHINE Filed June 2, 1938 4 Sheets-Sheet 1 .IIIIIIIILI! Nov. 19, 1940.

R. BECKER SEWING MACHINE Filed June 2, 1938 4 Sheets-Sheet 2 Nov. '19, 1940. BECKER 2,222,016

SEWING MACHINE Filed June 2, 1938 Sheets-Sheet 3 R. BECKER SEWING MACHINE Nov. 19, 1 940,

4 Sheets-Sheet 4 Filed June 2, 1938 3 mm c/wbcw Rudokk Becker Wifmss= Patented Nov. 19,- 1940 I UNITED STATES PATENT OFFICE SEWING MACHINE Rudolph Becker, North Plainfield, N. J., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New J ersey- Application June 2, 1938, Serial No. 211,345

16 Claims.

This invention relates to sewing machines and .more particularly to improved mechanism for effecting movement of the work through the machine during the operation thereof.

5. The invention has as a primary object to provide a sewingmachine having a feeding mechanism of which all of the actuating elements .are

subject to continuous and automatic lubrication and in which the lubricant is so confined and 10 controlled as to prevent it from soiling either the external portions of the machine or the work.

Stated more specifically, an object of the in-.

vention is to provide a sewing machine constructed with an oil-tight compartment having therein a feed-actuating mechanism which is of simplified construction; which is easy running and quiet in operation; which is self-lubricating and self-cooling, and in which the work-engaging face of the feed-dog'is maintained parallel with 20 the work-supportingsurface of the throat-plate In the accompanying drawings, Figure 1 isafront elevation of a sewing machine embodying the present invention. 35 Fig. 2 is a left end view of the machine shown in Fig. 1.

. Fig. 3 is a right end view of the machine shown in Fig. 1, with the hand-wheel and an and cover plate removed 40 Fig. 4' is a horizontal sectional view taken substantially on the line 4-4 of Fig. 1.

Fig. 5 is a bottom view of Fig. 1 with the bot tom plate removed. g Fig. 6 is a longitudinal vertical sectional view substantially on the line 6-6 of Fig. 4.

Fig. 7 is a transverse vertical sectional View substantially on theline 1-1 of Fig. 4. Fig. 8 is an enlarged vertical sectional view substantially on the line 8-8 of Fig. 4.

Fig. 9 is a detail vertical sectional view substantially on the line 9-9 of Fig. 4. v

Fig. 10 is a. vertical sectional view substantially on the line Ill-ll of Fig. 4, illustrating means for effecting a continuous flow of air through the machine base thereby to cool the oil in the oil reservoir therein.

Fig. 11 is an enlarged side elevation, partly in section, of an improved presser-foot, later to be described. I 5

. Fig. 12 is a detail sectional view illustrating an oil seal about the looper-shaft.

Referring more specifically to the drawings,- the invention is disclosed as embodied in a sewing machine comprising a base I, standard 2, overhanging arm 3'and head 4. A main driving shaft 5 is journaled lengthwise of the arm and carries at its rear end a-combined beltand hand-wheel 8. At its forward end, the shaft 5 actuates, through suitable mechanism designated '15 generally as I, a reciprocatory needle-bar 8 which is mounted in the head 4 and carries, at its lower end, an eye-pointed needle 9. Alsomounted in -the head 4,is a spring-pressed presser-barlll within the bifurcated lower end of which is secured, as by a clamp-screw H, the upright shank l2 of a. presser-foot l2. To enable the presserfoot to be tilted relative to its supporting bar II, as indicated, for example, in dotted lines in Fig. 11, and to maintain the foot in its tilted position, the foot carries opposed stop-screws l3 and I4 the heads of which are adapted to engage the opposite sides of the lower end Ill of the presserbar. By releasing the clamp-screw II and adjusting the stop-screws l3 and II the foot may be tilted relative to the bar III to cause either the toe-portion or the heel-portion to bear more heavily upon the work.- After the desiredadjustment has been made, the foot may be secured to the presser-bar In by again tightening the 5 clamp-screw II.-

The base I, standard 2, arm 3 and head 4 'arepreferably formed as a single casting, the base being in the nature ofan inverted pan closed at the bottom by a plate I 5 and gasket Hi. The 40 standard 2 is provided with a vertically arranged chamber l1 within which operates a belt l8 adapted to transmit .rotary motion from a pulley l9, secured to the main shaft 5,'to a similar pulley 20 secured upon the rear end of a shaft 2| journaled horizontally in bearings 22 and 23 provided bythe base I. To the unbroken upper surface I of the base I there is secured a horizontally disposed work-supporting plate 24, one

' end of which is formed to receive the standard 2.

The end 2| of the shaft 2|, remote from the pulley 20, projects through a bore 25 formed in the vertical end wall I of the base I, and carries a conventional chain-stitch loop-taker 26 which cooperates with the needle 8 in the formation of 66 stitches. Thus. rotation of the main shaft 5 effects reciprocation of the needle-bar and the needle carried thereby, and also, through the belt l8 and pulleys l9 and 2|), efiects rotation of the loop-taker 26 in timed relation with the reciprocations of the needle.

Cooperating with the presser-foot to effect step-by-step movements of the work between successive reciprocations of the needle, is a feeding mechanism including a feed-dog 21 which operates through a slot 28 in a throat-plate 29 secured in the work-plate 24, (see Fig. 5). This feed-dog is adapted to be given backward-and-forward and rising-and-falling movements such as are common in conventional four-motioned feeding mechanisms. Power to effect these movements is taken from the shaft 2| by mechanism located wholly within an oil-tight chamber 30 formed by the inverted pan-like base and the bottom plate I5. While this invention is shown and described in connection with a four-motioned feeding mechanism, it is to be understood that it is not limited to that type of feeding mechanism and that the use thereof with other types of feeding mechanisms is contemplated.

As shown most clearly in Figs. 2, 4 and 8, the feed-dog 21 is secured upon one endof a feedbar 3| by a screw 32 and held against turning relative thereto by having its shank 21 fitted into a slot 33 formed in a disk 33. The disk 33 is secured to a head 3| formed integral with the feed-bar, by screws 34. The feed-bar 3| is journaled in a bore 35 in a horizontally disposed Sleeve 36 formed integral with a depending rod 31. The rod 31 is slidingly mounted in a vertically arranged bearing sleeve 38 forming a part of an oscillatory feed-rocker 39. This feedrocker is journaled upon a shaft 46 mounted in bushings 4| secured in the base Formed integrally with the feed-rocker 39 is a slotted segmental arm 42 adapted to have operatively connected thereto, by a stud 42, the lower end of a pitman 43 having its upper end 43- embracing a crank or eccentric portion 44 formed on the shaft 2|. A portion of the stud 42 is fitted within the slot in the arm 42. Thus rotation of the shaft 2| will, through the elements 44, 43, 42, eflect oscillation of the feed-rocker 39 and thereby cause the feed-bar 3| and the feed-dog 21 carried thereby, to be moved back and forth transversely of the base I, thus giving to the feed-dog its feed-and-return strokes.

The amplitude of movement transmitted to the feed-dog from the crank 44 is dependent upon the point of connection of the pitman 43 and stud 42 with the segmental arm 42. This point may be shifted, thereby to vary the stroke of the feeddog, by the manipulation of a feed-adjusting lever 45 pivoted upon a screw 46 at the right end of the machine (as viewed in Fig. 1) and projecting through a slot 41 formed in the forward wall of the standard 2 (see Fig. 3). Intermediate its ends, the lever 45 is connected by a link 48 to an arm 49 secured upon the rear end of a rock-shaft 50, journaled in the base I parallel to the shaft 2|. At its opposite end the shaft 56 carries an arm 5| which is connected, by a link 52, to the stud 42 which connects the pitman 43 to the segmental arm 42. It will be apparent that shifting of the lever 45 will vary the position of the stud 42- in the slot in the segmental arm 42 and thereby vary the feeding stroke transmitted to the feed-dog. The lever 45 may be secured in its various positions of adjustment by a clampscrew 53 threaded upon the projecting find 45 of the lever 45 and adapted to engage a slotted cover-plate 54 secured upon the front face of the standard 2.

Rising and falling movements are transmitted to the feed-bar, in timed relation with its backward and forward movements, by a crank or eccentric portion 55 also provided by the shaft 2| (see Figs. 4 and 9). This crank is embraced by a block 56 having a bore 51 slidingly receiving one end of a bar 58. The other end of the bar 58 is slidingly mounted in a sleeve 59, pivoted, by means of a trunnion 60,.in a bearing block 6| secured in the end-wall l of the base Intermediate its ends the bar 58 is formed with an enlarged portion or clamp-block 62 having a transverse bore 63 adapted to receive the feed-bar 3| which is held against endwise movement therein by a set-screw 64 (see Figs. 8 and 9). The block 62 is split, asat 65 and a clamp-screw 66 serves to draw the opposite sides together thereby to firmly grasp the feed-bar 3| therein. As the feed-rocker 39 is oscillated about the shaft 40 to give the feed-dog its feed-and-return movements, the bar 58 slides back and forth in the block 56 and the sleeve 59. Rotation of the crank 55 with the shaft 2| causes the bar 58 to be oscillated about the axis of the trunnion 60 and as the clamp-block 62, carried by the bar, embraces the feed-bar 3| is causes that element, and the feed-dog carried thereby, to be moved up and down, successively into and out of engagement with the work held upon the workplate 24 by the presser-foot l2.

Thus it will be apparent that the mechanism above described will give to the feed-bar 3| and the feed-dog 21 backward-and-forward and rising-and-falling movements such as are common to so-called four-motioned feeding mechanisms.

In this type of feeding mechanism it is highly desirable that the work-engaging face of the feed-dog be maintained parallel with the worksupporting surface of the throat-plate during the entire feeding stroke of the feed-dog. Many complicated and costly constructions heretofore have been provided for that purpose. That result has been attained in the present construction by merely arranging the bar 58 at an inclination relative to the work-supporting surface of the throat-plate 29 and work-plate 24, as seen most clearly in Fig. 9. With this construction, as the feed-dog is moved from front to rear to advance the work, its tendency to drop, after the feedlift eccentric has passed through its uppermost position, is counteracted by the rising movement of the inclined bar 58 as it slides upwardly in the block 56 and sleeve 59.

To lighten the load on the feed-driving mechanism and toeliminate vibration in the machine, the feed-rocker has been balanced by means of a counter-weight 61 attached thereto at the side of the axis of the rocker opposite the segmental arm 42. This counter-weight statically balances the feed-rocker and therefore very little power is required to give to it its rocking movements. Likewise, during the running of the machine, the reactionary forces transmitted to the bearings (which forces heretofore have set up vibrations in sewing machines) are counteracted or neutralized with the result that the present machine may be operated at high speed with little or no vibration.

The lower portion of the chamber 30 constitutes a reservoir or basin into which oil 0 is placed to the level indicated at L in Figs. 6 and 7. During the operation of the machine the arm 42 and the counterweight 61 forcibly contact with the oil and thereby splash it about the interior of the chamber 30, thus splash-lubricating the feed-actuating mechanism, all of which is 10- cated within the chamber.

As shown most clearly in Figs. 4 and 8, the feed bar 3| extends through an opening 88 formed in the end-wall l of the base I. This opening is of sufficient size to permit the feed-bar to have the necessary vertical and horizontal movements to give the feed-dog 21 the usual rising-and-falling and backward-andforward movements common to four-motion feeding mechanisms.

An-important feature of this invention is the sealing of the opening 88 to prevent lubricant from escaping therefrom. This has been accomplished by making the inner face-f of the wall l relatively smooth and arranging itQin a plane substantiallyparallel to the vertical plane in which the feed-dog is moved, and maintaining against said face} a sealing member 89 carried by the feed-bar 3| and partaking 'of the movements thereof. The member 69 is sufliciently large to cover the opening 68 in all of the posi- 'tions of the feed-bar and preferably consists of a sheet metal disk surroundingthe feed-bar 3| and maintained in contact with the surface I by means of a bee-hive spring 80 inserted between the disk and the clamp-block 62.

In its outer face, the wall is formed with a substantially rectangular cavity 18 the walls 10"- of which are undercut as best shown in Figs. 4

and 8. The inner wall 10 of the cavity 10 is parallel with the face of the wall I, and is engaged by the inner face 3| of the head 3| formed on the feed-bar 3|. Like the disk 69, the head 3| is largerthan the opening 88 through which the feed-bar extends and therefore it serves as a second means for preventing escape 40 of oil from the chamber. The cavity I0 is sufllciently larger than the head .3|.to permit the latter to partake of the four-motion feeding movements. Shouldany oil find its way past the disk 69 and past the face 3| of the head 3| it will be thrown oil into the cavity 10 and will gravitate to the lower portion thereof from which it will be conducted back into the chamber 30 by wicking II fitted within an inwardly and downwardly inclined duct 12 formed in the wall l To prevent oil from escaping from the chamber 30 through the bearing 25 for the shaft 2|, .1 have provided on the shaft- 2|, an oil-sling 80 in the form of a truncated cone a portion of .55 which fits within a countersink 8| (see Fig. 12), formed in the end wall I. The end wall I is also formed with a cavity 82 about the end 2| of the shaft 2| and a downwardly and inwardly inclined duct 83, connecting the cavity with the o chamber 30. The duct 83 is preferably filled with wicking 84. By reason of this construction should any oil pass the oil-sling 8| it will be collected in the cavity 82 and returned to chamber 30.

From the foregoing -it will be perceived that the entire feed-actuating mechanism is located within an oil-tight chamber and is constantly splash-lubricated during the operation of the machine.

Obviously during high-speed rimning of the machine the friction between the relatively movable parts of the machine in the chamber 30 will generate a certain amount of heat. This heat is absorbed by the oil which is constantly splashed 15 over the parts. Some of the heat in the oil is absorbed by the nietalof the machine base and is radiated thereby into the surrounding air. To further reduce the temperature of the oil, so that the-work-plate and other parts of the machine will not become heated to a temperature that is objectionable to the operator, I have provided a 1| and an outlet port I2. These ports communicate with a chamber I3 formed within the lower portion of the standard 2, within whichchamber is arranged an air-pump I4 in the nature of a rotary fan secured upon the shaft 2|. During operation of the machine the pump draws fresh air into the chamber 38 from the atmosphere through port and'discharges other air, which has absorbed acertain amount of heat, through port 12. This constant circulation of relatively cool air through the chamber -30 carries away the excess heat and maintains the desired temperature within the chamber.

To enable the operator to ascertain the amount of oil in the chamber 38, agauge rod 15 is inserted therein. This gauge rod is carried by a screw 16 tightly threaded into an aperture in the upper wall of the base (see Fig. '7). This screw may be unscrewed and the rod withdrawn for inspection while the machine is at rest but during the running of the machine the screw seals the hole and maintains the chamberv 30 oil-tight. i

Having thus set forth the nature of the invention what I claim herein is:

1. A sewing machine comprising a frame pro-.

viding a substantially closed chamber having an opening in one wall thereof, a four-motioned work-feeding mechanism comprising a member extending through said opening. and movable vertically and horizontally therein, a work-feeding element actuated-by the outer endof said member, means located within said chamber for giving to said member its vertical and horizontal feed-actuating motions, means for automatically lubricating said feed-actuating mechanism, and means efiecting an oil-tight seal about said memher where it emerges from .said chamber.

2. A sewing machine comprising a frame providing a substantially closed chamber having an opening in one wall thereof, stitch-forming mechanism supported by said frame, and a fourmotioned work-feeding mechanism comprising a feed-bar extending through said opening, a feeddog actuated by the outer end of said feed-bar, feed-actuating mechanism located within said chamber for giving to said feed-bar itsfour motions, means. for automatically lubricating said feed-actuating mechanism, and a member carried by said feed-bar and engaging said wall about said opening for efiecting an oil-tight seal about said feed-bar where it emerges from said chamber.

3. A sewing machine comprising a frame providing a substantially closed chamber having an opening in one wall thereof, stitch-forming mechanism supported by said frame and a fourmotioned work-feeding mechanism comprising a feed-bar extending through said opening, a feed-dog actuated by the outer end of said feedbar, feed-actuating mechanism located within said chamber for giving to said feed-bar its four motions, means within said chammer and operative during running of the machine to effect continuous lubrication of said feed-actuating mechanism, and a member carried by said feedbar and maintained in contact with said wall and closing said opening during the operation of the machine to effect an oil-tight seal about said feed-bar where it emerges from said chamber.

4. A sewing machine comprising a frame providing a substantially closed oil-containing chamber having an opening in one wall thereof, stitchforming mechanism supported by said frame, and a four-motioned work-feeding mechanism comprising a feed-bar extending through said opening, a feed-dog actuated by the outer end of said feed-bar, feed-actuating means located within said chamber for giving to said feed-bar its four motions, means within said chamber and operative during running of the machine to contact with the oil in said chamber to splash-lubricate said feed-actuating means, and means effecting an oil-tight seal about said feed-bar where it emerges from said chamber.

5. A sewing machine comprising a frame providing a substantially closed oil-containing chamber having an opening in one vertical wall thereof, a four-motioned work-feeding mechanism comprising a member located partially within said chamber and having an end extending substantially horizontally through said opening and movable vertically and horizontally therein, a feed-dog actuated by the outer end of said member, feed-actuating means located within said chamber for giving to said member feeding motions, a portion of said feed-actuating means contacting with the oil in said chamber to effect splash-lubrication thereof; and means preventing oil from escaping from said chamber about said member where it extends through said opening.

6. A sewing machine comprising a frame pro-,.

viding a substantially closed chamber including an upright wall having an opening therein, stitchforming mechanism supported by said frame, and a work-feeding mechanism comprising a feedbar extending through said opening and having an enlarged portion contacting with the outer surface of said wall, a feed-dog actuated by the outer end of said feed-bar, means located within said chamber for giving to said feed-bar its feeding motions, means within said chamber effecting automatic lubrication of said feed-actuating mechanism, and means including a member carried by said feed-bar and maintained in contact with the inner face of said wall about said opening for effecting an oil-tight seal about said feed bar where it emerges from said chamber.

7. A sewing machine comprising a frame providing a substantially closed chamber including an upright wall having a cavity in its outer face and a transverse opening in line with said cavity, stitch-forming mechanism supported by said frame, and a four-motioned work-feeding mechanism comprising a feed-bar extending through said opening and having an enlarged portion arranged within said cavity and engaging the outer face of said wall and closing said opening about said feed-bar, a feed-dog actuated by the outer end of said feed-bar, means located within said chamber for giving to said feed-bar its four motions, means within said chamber effecting automatic lubrication of said feed-actuating mechanism, and means including a plate carried by said feed-bar and spring means acting on said plate to maintain it in contact with the inner face of said wall about said opening for effecting an oil-tight seal about said feed-bar where it emerges from said chamber.

8. A sewing machine as set forth in claim 'I in which the peripheral walls of said cavity diverge from the outer face of the upright wall of the chamber and in which a drain duct connects the lower portion of said cavity with the chamber to return to the latter any oil which might pass through said opening.

9. A sewing machine comprising aframe providing a substantially closed chamber including an upright wall affording parallel inside and outside faces and having an opening therethrough, a work-feeding mechanism including a feed-bar extending through said opening, a feed-dog secured to the outer end of said feed-bar and means within saidchamber for giving to said feed-bar and feed-dog four-motion feeding movements in planes parallel to the parallel faces of said upright wall, the opening in said wall being sufliciently large to permit said feed-bar to partake of its four motions, means within said chamber for effecting automatic lubrication of said feed-actuating mechanism, and means carried by said feed-bar and engaging the inside and outside faces of said upright wall to prevent escape of lubricant through said opening.

10. A sewing machine comprising a frame having a chamber formed in its base portion comprising substantially horizontal top and bottom walls and upright side and end walls, one of said upright walls having an opening therein; a four motioned work-feeding mechanism' including a vertically and horizontally movable feed-bar, substantially smaller in cross-section than said opening, located partially within said chamber and having a portion projecting through the opening in said upright wall, a feed-dog actuated by the outer end of said bar, and feed-actuating mechanism within said chamber for giving to said feed-bar vertical and horizontal movements, means within said chamber for automatically lubricating said feed-actuating mechanism, and means movable with said feed-bar for effecting an oil-tight seal about said bar where it emerges from said chamber.

11. A sewing machine comprising a frame having a base portion including top, side, and end walls, one of said end walls having an opening therein, a plate secured to the lower edges of said side and end walls and cooperating therewith and with said top wall to form a substantially closed oil-containing chamber; stitch-forming mechanism supported by said frame; a work-feeding mechanism including a vertically and horizontally movable member located partially within said chamber and having a portion projecting through the opening in said end wall, a feed-dog actuated by the outer end of said member, feed-actuating mechanism within said chamber for giving fourmotioned feeding movements to said member, means within said chamber contacting with the oil therein to effect splash-lubrication of said feedactuating mechanism, and means effecting an oil-tight seal about said bar where it emerges from said chamber.

12. A sewing machine comprising a frame having an oil-containing chamber formed in its base portion comprising substantially horizontal top and bottom walls and upright side and end walls,

,feeding movements to said feed-bar, means within said chamber contacting with the oil therein to effect splash-lubrication of said feed-actuating.

mechanism, and a member carried by said feedbar and engaging the wall about said opening for eflecting, an oil-tight seal about said feed-bar where it emerges from said chamber.

13. A sewing machine comprising a frame providing a substantially closed chamber, a rotary shaft journaled in said frame and extending through said chamber feed-actuating mechanism located within said chamber, movable means contacting with the oil in said chamber to eflect automatic lubrication of said feed-actuating mechanism and means including intake and exhaust ports in said frame and a rotary pump on said shaft withinsaid chamber for effecting a constant circulation of air through said chamber during operation of the machine. t

.14. A sewing machine comprising a frame providing a substantially closed oil-containing chamber and an intake port and an exhaust port connecting the chamber with' the atmosphere, a ro-' tary shaft iournaled in said frame and extending through said chamber, feed-actuating mechanismlocated within said chamber and actuated from said shaft, means actuated by said shaft contacting with the oil in said chamber for effecting splash-lubrication. of said feed-actuating 5 mechanism during the operation of the machine, 1 and rotary means within said chamber operative during the operation of the machine for drawingair into said chamber through said intake port and discharging air from said chamber through 10 said exhaust port.

15. A sewing machine as set forth in claim 14 in which the means for effecting a circulation of air through the chamber comprises a rotary pump secured to the rotary shaft within said chamber 1 adjacent said intake and exhaust ports.

16. A sewing machine having a frame formed with an oil splash lubricating chamber, a feedbar supported in said chamber, oil splashing means in said chamber, means in said chamber 20 to impart feed-and return and rising-and-falling movements to said feed-bar, said chamber having an opening therein and said feed-bar having an extension passing through said opening transversely of the path of movement of said feed- 25 bar, a feed-dog carried by said extension exteriorly of said chamber,and a plate larger than said opening and carried by said feed-bar in position to cover said opening at all times while in sliding engagement with a planar wall-portion of said 30 chamber surrounding said opening.

aunorrn Boom 

